This invention relates generally to a drive system for the lint cleaners, or strippers, of a cloth napper machine, and more specifically to an overload release arrangement for such drive system.
A pair of rotating napper strippers in a cloth napper machine conventionally are driven through gearing that enables the stripper driving shafts to be driven synchronously with a rotating annular carrier that carries rotating napper rollers on its periphery. The stripper drive shafts are contra-rotating and driven in timed relationship with the carrier. The napper rollers carry wire card cloth on their surfaces, the cloth comprising slanted wire needles that are closely spaced to each other. The strippers are each in the form of a pair of radially extending wire brushes mounted on the stripper drive shafts in diametrically opposed relationship. The strippers clean the lint from the napper rollers by brushing a card cloth material in the same direction that it is slanted. Therefore, each napper roller, which itself is rotating about its own axis, is cleaned by one or the other of the napper strippers, depending on its own direction of rotation and the slant of its respective card cloth. A specific napper roller will be cleaned only by one specific stripper that is rotating in a proper sense to clean a card cloth from the inside outwardly. The napper rollers must not be contacted by the wrong napper stripper or the card cloth will be dulled and burred by the cleaning brushes.
Because of the operating relationship of the elements, it is critical that the timing of the napper strippers be maintained with respect to the rotating carrier and rotating nappers at all times. Any disruption of the synchronous operation of the elements will create difficulties and expenses on the part of the machine operator and result in an inferior napper fabric produced by the machine.
It is not an uncommon occurrence in a napper machine that the fabric being napped is caught up in one or more napper rollers or is simply caught upon and dragged around with the carrier. When this happens, usually the fabric is brought into contact with one or both of the napper strippers and caught up therein before the machine can be shut down. If no overload release means were provided for the napper stripper drive shafts, the stripper drive gearing would be damaged.
Overload reliefs for napper stripper drive trains are therefore provided to prevent damage to the gearing and the fabric being napped. An early teaching of providing such an overload release for a napper stripper is illustrated in U.S. Pat. No. 1,154,350, where a single relief is shown provided in the gear train driving a pair of napper strippers.
The present invention is intended to provide an improvement over the prior art overload clutch release systems used for napper strippers and is a specific adaptation of an overload release clutch described in U.S. Pat. No. 2,259,824 issued Oct. 21, 1941.